The known near-eye display devices, in particular those with propagation of light rays in the open air, have non-negligible drawbacks. Indeed, in these devices, the mirrors used are large, thus contributing to increasing the bulk of said devices. The weight of these devices is also a drawback. Such devices are in particular described in documents US 2012/0212400 A1 or FR 2,941,786 A1.
Document FR 2,983,976 also teaches an optical guide with superimposed guide elements. The lamellar guide elements are contiguous by one of their faces and separated by a semi-reflective coating on at least part of their length. Precise positioning of the semi-reflective coating makes the manufacturing of such optical guides complex and costly. Furthermore, the contiguous assembly of the two guide elements must be free of dimensional irregularities or air pockets to guarantee that the optical guide works perfectly.
It is also difficult to control the losses experienced by the optical signals propagating through such optical guides.
The known optical systems, in particular those including such optical guides, often procure a limited field of view in at least one direction, typically a field of view of 26° (horizontal direction)×20° (vertical direction). This is quite often a major drawback in their fields of use.